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DNAseq analysis of a genome-wide loss-of-function CRISPR/Cas9 library in haploid human embryonic stem cells transfected with a methylated construct containing the FXS-related mutation upstream to an EGFP reporter gene

ABSTRACT: The primary mechanism causing Fragile X syndrome (FXS) is the expansion and silencing of a repetitive CGG sequence in the 5’-UTR of the FMR1 gene. To identify novel epigenetic pathways involved in FXS pathogenesis, we have established a model system for FMR1 silencing using a construct containing the FXS-related FMR1 CGG expansion upstream to an EGFP reporter gene. This construct was methylated in vitro and introduced into a genome-wide loss-of-function (LOF) library established in haploid human pluripotent stem cells. Library cells were then sorted to GFP-positive and GFP-negative populations. The analysis of the changes in abundance of mutants between the GFP-positive and GFP-negative populations has yielded a list of candidate genes whose functional loss reversed the methylation-induced silencing of the expanded FMR1 5'-UTR sequence.

ORGANISM(S): Homo sapiens

PROVIDER: GSE182551 | GEO | 2022/06/01

REPOSITORIES: GEO

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| EGAS00001001737 | EGA